Skip to content
PatentBrief
Get alertsTop ↑

How Brain-Inspired Computers Learn and Unlearn Information

This patent describes a method for a brain-like computer network to learn associations between different inputs and then specifically unlearn mistakes or 'false positives' using a unique feedback mechanism.

Granted 2022ActiveExpires 2039Owned by International Business MachinesInvented by Dharmendra S. Modha

Original patent title: “Unsupervised, supervised and reinforced learning via spiking computation”

Plain-English explanation by SahiLast reviewed · October 25, 2026

This patent describes a method for a brain-like computer network to learn associations between different inputs and then specifically unlearn mistakes or 'false positives' using a unique feedback mechanism. Granted to International Business Machines in 2022 with 23 claims, and it is expected to expire in 2039.

Coverage

What does this patent actually cover?

This patent describes a way for a special type of computer network, called a neural network, to learn by associating features from two different inputs. For example, if you show it a picture of a cat (first input) and the sound of a meow (second input), it learns to connect them. The process involves feeding the first input to a 'first neuron population' and the second input to a 'third neuron population.' As these inputs travel through the network along 'pathways,' the network extracts their features. The clever part is how it corrects errors: it 'unlearns false positives' by taking copies of 'firing events' (like signals from brain cells) from certain parts of the network and propagating them back through 'additional pathways.' This unlearning uses a 'second learning rule,' which can be an 'anti-STDP' or 'anti-Hebb' rule, effectively weakening incorrect connections.

The gap

What does this patent NOT cover?

  • Does not cover traditional artificial neural networks that do not use 'spiking computation' or 'firing events' as described.
  • Does not cover learning systems that correct errors without explicitly propagating 'copies of firing events' through 'additional pathways' for unlearning.
  • Does not cover methods of unlearning that do not employ an 'anti-learning rule' such as anti-STDP or anti-Hebb.
  • Does not cover neural networks that only process a single input without associating features between two distinct inputs.
  • Does not cover systems where the unlearning process is not initiated by firing events from the second and fourth neuron populations.

These exclusions are unique to PatentBrief — derived from the actual claim language, not patent-office boilerplate.

Key facts

Patent numberUS 11481621
StatusActive
FieldAI & Machine Learning
AssigneeInternational Business Machines
InventorDharmendra S. Modha
Filed2019
Granted2022
Expires2039
Claims23
Times cited0
LitigationNone on record
Value · $47K–$150KMinimal

What made this novel

The truly novel aspect is the explicit, structured mechanism for 'unlearning false positives.' Instead of just adjusting weights during forward passes, the patent describes copying 'firing events' and sending them back through dedicated 'additional pathways' with an 'anti-learning rule' (like anti-STDP) to specifically weaken incorrect associations. This provides a targeted way to forget wrong connections.

The Patent Drawing

Representative patent drawing for Unsupervised, supervised and reinforced learning via spiking computation (US 11481621)
Representative figure · US 11481621All figures on Google Patents →
Unsupervised, supervised and r…(Primary claim)artificial intelligencemachine learningsemiconductorssoftwareconsumer electronics

Schematic visualization of the patent's claim structure. Hand-drawn diagrams in progress for each landmark patent.

Where you've seen this

Real-world examples

01

IBM's TrueNorth neuromorphic chip

02

Research in low-power AI for edge devices

03

Brain-inspired computing hardware

04

Robotics learning systems requiring error correction

Why it matters

The bigger picture

This technology is important because it addresses a fundamental challenge in artificial intelligence: making learning systems more efficient and robust. By providing a specific mechanism for 'unlearning,' it allows neural networks to refine their knowledge and correct mistakes, which is crucial for complex tasks. This approach, using brain-inspired 'spiking computation,' could lead to more energy-efficient AI hardware, especially for devices that need to learn on the go.

Filed

August 16, 2019

Granted

October 25, 2022

Market context

Who's building on this

Companies in this space

International Business Machines Corp. (IBM), the assigneeassigneeThe entity that owns the patent — usually the inventor's employer or a company.Read more →, has been a leader in neuromorphic computing with its TrueNorth chip, which implements spiking neural networks. Other major technology companies and academic research institutions are also actively exploring spiking neural networks for their potential in energy-efficient AI, particularly for edge computing applications where power consumption is critical.

Market impact

This patent contributes to the growing field of neuromorphic computing, which aims to create AI hardware and software that mimic the brain's efficiency. While still an emerging area compared to conventional deep learning, advancements in unlearning mechanisms like this could accelerate the development of more robust and adaptive AI. This could lead to a new generation of AI chips and algorithms, particularly impacting sectors requiring low-power, on-device intelligence.

Claim 1 — Plain English

What this patent covers

This patent describes a way for a special type of computer network, called a neural network, to learn by associating features from two different inputs. For example, if you show it a picture of a cat (first input) and the sound of a meow (second input), it learns to connect them. The process involves feeding the first input to a 'first neuron population' and the second input to a 'third neuron population.' As these inputs travel through the network along 'pathways,' the network extracts their features. The clever part is how it corrects errors: it 'unlearns false positives' by taking copies of 'firing events' (like signals from brain cells) from certain parts of the network and propagating them back through 'additional pathways.' This unlearning uses a 'second learning rule,' which can be an 'anti-STDP' or 'anti-Hebb' rule, effectively weakening incorrect connections.

The clever bit

The truly novel aspect is the explicit, structured mechanism for 'unlearning false positives.' Instead of just adjusting weights during forward passes, the patent describes copying 'firing events' and sending them back through dedicated 'additional pathways' with an 'anti-learning rule' (like anti-STDP) to specifically weaken incorrect associations. This provides a targeted way to forget wrong connections.

What it does not cover

  • Does not cover traditional artificial neural networks that do not use 'spiking computation' or 'firing events' as described.
  • Does not cover learning systems that correct errors without explicitly propagating 'copies of firing events' through 'additional pathways' for unlearning.
  • Does not cover methods of unlearning that do not employ an 'anti-learning rule' such as anti-STDP or anti-Hebb.
  • Does not cover neural networks that only process a single input without associating features between two distinct inputs.
  • Does not cover systems where the unlearning process is not initiated by firing events from the second and fourth neuron populations.

Patent timeline

Filing

Application submitted to the patent office

Publication

Application published, typically 18 months after filing

Grant

Patent officially issued

Expiration

Patent enters public domain

PatentBrief Score

Impact Score

Early stage

Citation count

0/40

No citations yet

Claim breadth

15/20

Broad claimsclaimsThe numbered statements at the end of a patent that legally define what the inventor owns.Read more →

Recency

20/20

Granted within 5 years

Assignee scale

0/20

Independent or smaller assigneeassigneeThe entity that owns the patent — usually the inventor's employer or a company.Read more →

PatentBrief Impact Score — based on citation count, claim breadth, recency, and assignee scale. Not a legal assessment.

Heuristic Value Estimate

What this patent might be worth

Minimal

$47K – $150K

Midpoint $94K · 12.8 yr remaining · industry ×1.6

Adjust inputs →

Heuristic only — blends forward/backward citation counts, claim scope, time remaining, litigation history, and CPC-derived industry baseline. Real valuations need a professional appraisal.

Claim text not yet imported for this patent

The original legal language

Original claims

23 claims as filed with the patent office.

Concepts involved

ClaimPrior artNon-obviousnessNoveltySpecificationAssigneePatent term

Citations

Patent lineage

Cites earlier patents

53

earlier patents this invention cites as foundations

View prior art →

Cite this patent

Modha, D. S. (2022). How Brain-Inspired Computers Learn and Unlearn Information (U.S. Patent No. 11,481,621). U.S. Patent and Trademark Office. https://patentbrief.org/patent/us/11481621/unsupervised-supervised-and-reinforced-learning-via-spiking-computation

Auto-generated from the patent record. Double-check author order and the issue date against the official USPTO document before submitting.

Embed

Add this patent to your site

Drop this plain-English patent card into any blog post or article — free, no signup. It always links back to the full breakdown here.

<div data-patentlens-widget data-patent-number="US11481621"></div>
<script src="https://patentbrief.org/embed.js" async></script>

Stay in the loop

Get a weekly digest of new patents.

One email per week. No spam. Unsubscribe anytime.

Keep exploring

Related patents you should know

US 4683195 · 1987

How to Make Billions of Copies of a DNA Segment

This patent describes the Polymerase Chain Reaction (PCR), a method to rapidly create many copies of a specific piece of DNA or RNA, enabling its detection and analysis.

Cetus Corp

US 8697359 · 2014

How to Edit Genes in Human Cells Using an Engineered CRISPR System

This patent describes an engineered CRISPR-Cas9 system for precisely cutting DNA in eukaryotic cells to change how genes work, opening the door for gene editing in complex organisms.

Massachusetts Institute of Technology

US 7657849 · 2010

How the iPhone's Slide-to-Unlock Gesture Works

Apple's 2010 patent describes unlocking a device by dragging a specific graphical image across the touchscreen along a predefined path, a gesture that became iconic with the original iPhone.

Apple Inc

US 4733665 · 1988

How Doctors Implant a Permanent Stent Using a Balloon

This patent describes the method for placing a permanent, expandable wire mesh tube inside a blood vessel or other body tube using a balloon-tipped catheter to widen it and keep it open.

Expandable Grafts Partnership

US 4965188 · 1990

How to Make Many Copies of a DNA Piece with Heat

This patent describes the Polymerase Chain Reaction (PCR) method, a technique to make millions of copies of a specific DNA segment using a heat-resistant enzyme and repeated temperature changes.

Cetus Corp

US 4235871 · 1980

How to Encapsulate Active Materials in Lipid Bubbles Efficiently

This patent describes a method for trapping biologically active substances inside tiny, multi-layered fat bubbles called liposomes, using a specific water-in-oil emulsion and gel-forming process to improve how much material gets captured.

Individual

Semantically similar

You might also find these interesting

SEARCH ALL

More to explore

More in AI & Machine Learning

Browse all AI & Machine Learning

New to patents?

What is a patent?How to read a patentAnatomy of a claimHow strong is this patent?What the citations meanWhat it doesn't coverPatent glossary
Explore the landscape:artificial intelligence patents →machine learning patents →semiconductors patents →

Common Questions

Frequently Asked Questions

What does How Brain-Inspired Computers Learn and Unlearn Information cover?

This patent describes a method for a brain-like computer network to learn associations between different inputs and then specifically unlearn mistakes or 'false positives' using a unique feedback mechanism.

Who owns patent US 11481621?

International Business Machines owns this patent, granted in 2022.

When does this patent expire?

This patent is expected to expire on August 16, 2039, when the invention enters the public domain.

What problem does this patent solve?

This technology is important because it addresses a fundamental challenge in artificial intelligence: making learning systems more efficient and robust. By providing a specific mechanism for 'unlearning,' it allows neural networks to refine their knowledge and correct mistakes, which is crucial for complex tasks. This approach, using brain-inspired 'spiking computation,' could lead to more energy-efficient AI hardware, especially for devices that need to learn on the go.

What does this patent NOT cover?

Does not cover traditional artificial neural networks that do not use 'spiking computation' or 'firing events' as described.

Same assignee

More from International Business Machines

View all →
US 12412637·2025

Computer Model Designs Proteins by Matching Structure to Sequence

US 12340293·2025

How a System Finds and Creates Machine Learning Models

US 11087204·2021

Making AI Chips Faster with Multiple Readers for Stored Data

US 10956815·2021

How to Fix Faulty Memory Cells in AI Chips

Patent monitoring

Get notified when International Business Machines files a new patent

Get notified when this company files a new patent. Weekly digest · Confirm via email · Unsubscribe anytime.

Last reviewed: October 25, 2026 · PatentBrief is not a law firm and this is not legal advice.